EURURO Vol. 71 No. 4

predictive of death from RCC (HR: 1.37; 95% CI, 1.34–1.42;

0.001). Observed CSS rates and the competing risk–

adjusted rates as stratified by SSIGN score are summarized

Table 2 ,

with observed estimates illustrated in

Figure 1

Among patients in the contemporary RN cohort,

595 patients had died at the time of last follow-up including

373 who died from RCC. Median duration of follow-up for

the 443 patients alive at last follow-up was 9.2 yr (IQR: 6.3–

12.1). Each unit increase in SSIGN score was associated with

a HR of 1.37 (95% CI, 1.33–1.40;

0.001) for predicting

death from RCC, with a bootstrap-corrected C-index of

0.84. After adjusting for the competing risk of non-RCC

death, higher SSIGN scores again remained predictive of

death from RCC (HR: 1.35; 95% CI, 1.30–1.39;

0.001).

Table 3

summarizes the observed CSS rates and the

competing risk–adjusted rates as stratified by SSIGN score,

with observed estimates illustrated in

Figure 1 b

At last follow-up, 154 patients in the contemporary PN

cohort had died including 30 who died from RCC. Median

follow-up for the 613 patients alive at last follow-up was

7.6 yr (IQR: 5.5–10.1). Each unit increase in SSIGN score was

associated with an HR of 1.70 (95% CI, 1.53–1.90;

0.001)

for predicting death from RCC, with a bootstrap-corrected

C-index of 0.82. Adjusting for the competing risk of non-RCC

death, higher SSIGN scores remained predictive of death

from RCC (HR: 1.70; 95% CI, 1.51–1.93;

0.001). Observed

CSS rates and the competing risk–adjusted rates as

stratified by SSIGN score are summarized in

Table 4

and

illustrated in

Figure 1

3.3.

Era of treatment and metastatic disease

We noted that survival within each SSIGN scorewas higher in

patients managed in the contemporary RN cohort compared

with the original RNcohort

( Fig. 1

a and1b). In amultivariable

setting, more recent era of treatment (1999–2010 compared

with 1970–1998) was significantly associatedwith a reduced

risk of death from RCC (HR: 0.53; 95% CI, 0.46–0.60;

0.001) even after adjusting for SSIGN score (HR: 1.40;

95% CI, 1.37–1.42;

0.001). When patients in the original

and contemporary RNcohortswere stratified by the presence

of metastatic disease (M0 vs M1), we noted that SSIGN score

Table 2 – Cancer-specific survival by stage, size, grade, and necrosis (SSIGN) score for patients in the original radical nephrectomy cohort:

observed and competing risk–adjusted rates

Cancer-specific survival rate

s *

Score

Year 1

Year 3

Year 5

Year 7

Year 10

Year 15

0–1

379

100; 100 (361)

99; 99 (335)

99; 99 (314)

98; 98 (285)

96; 97 (239)

94; 95 (164)

221

99; 99 (207)

96; 96 (190)

94; 95 (174)

90; 91 (152)

86; 88 (133)

81; 85 (101)

196

97; 97 (185)

90; 91 (161)

88; 89 (149)

82; 84 (130)

75; 78 (101)

62; 70 (65)

199

95; 95 (178)

87; 87 (152)

78; 80 (127)

68; 72 (110)

63; 68 (83)

48; 58 (41)

150

88; 89 (129)

69; 70 (97)

61; 62 (82)

54; 56 (69)

45; 49 (51)

40; 46 (29)

85; 85 (71)

68; 68 (56)

53; 54 (43)

47; 48 (37)

40; 42 (28)

33; 36 (22)

193

77; 78 (147)

48; 50 (88)

38; 40 (66)

29; 32 (50)

23; 27 (37)

18; 23 (25)

65; 66 (39)

34; 36 (20)

21; 23 (11)

15; 18 (7)

6; 10 (2)

58; 58 (56)

25; 27 (24)

18; 19 (17)

15; 16 (13)

12; 14 (11)

9; 11 (7)

155

36; 37 (53)

11; 13 (15)

7; 10 (10)

4; 7 (6)

4; 7 (5)

2; 6 (2)

RCC = renal cell carcinoma.

Two rates are presented. The first is the cancer-specific survival rate estimated using the Kaplan-Meier method; the second is the rate after accounting for the

competing risk of death from non-RCC causes. Number of patients at risk is denoted in parentheses.

Total = 1737; 58 patients excluded for unknown cause of death.

Table 3 – Cancer-specific survival by stage, size, grade, and necrosis (SSIGN) score for patients in the contemporary radical nephrectomy

cohort: observed and competing risk–adjusted rates

Cancer-specific survival rate

s *

Score

Year 1

Year 3

Year 5

Year 7

Year 10

Year 15

0–1

161

100; 100 (157)

100; 100 (147)

99; 99 (127)

99; 99 (104)

97; 98 (65)

97; 98 (10)

100; 100 (81)

99; 99 (72)

97; 98 (65)

97; 98 (57)

97; 98 (33)

90; 92 (4)

129

100; 100 (125)

99; 99 (114)

98; 98 (101)

97; 98 (76)

89; 91 (42)

89; 91 (10)

99; 99 (78)

92; 92 (66)

88; 88 (53)

84; 86 (44)

80; 82 (26)

71; 77 (3)

102

97; 97 (97)

86; 86 (80)

74; 75 (61)

68; 70 (38)

59; 63 (20)

49; 56 (3)

92; 92 (34)

76; 76 (28)

70; 71 (23)

70; 71 (18)

50; 53 (8)

40; 45 (1)

127

87; 87 (108)

62; 63 (72)

51; 54 (52)

46; 49 (31)

45; 48 (20)

21; 35 (1)

79; 79 (10)

35; 43 (4)

27; 36 (3)

18; 29 (2)

108

78; 78 (81)

46; 48 (45)

35; 38 (29)

29; 32 (18)

20; 26 (5)

156

59; 59 (90)

31; 32 (46)

15; 16 (21)

9; 11 (10)

6; 8 (7)

NA = not applicable because no patients were left at risk; RCC = renal cell carcinoma.

Two rates are presented. The first is the cancer-specific survival rate estimated using the Kaplan-Meier method; the second is the rate after accounting for the

competing risk of death from non-RCC causes. Number of patients at risk is denoted in parentheses.

Total = 1002; 36 patients excluded for unknown cause of death.

E U R O P E A N U R O L O G Y 7 1 ( 2 0 1 7 ) 6 6 5 – 6 7 3

668